The present invention relates to a power-driven pincer-type tool holder for use in handling apparatuses.
The term "handling apparatus" designates an apparatus which performs movements under program control in a plurality of degrees of freedom. A well known example is an automatic welding apparatus for spot welding of vehicle bodies. For this purpose, the vehicle body or, more generally, the work piece is supported in a predetermined position whereby a spatial reference coordinate system is defined according to which the welding apparatus is programmed. During spot welding, two electrodes act upon the work piece with equal and counter-directed forces so that the work piece is not deformed by bending or torsional stress.
It is an object of the present invention to provide a tool holder for such handling apparatuses which permits the implementation of operations where unidirectional forces may occur.